递归生成树形结构（后端代码）util工具类，直接使用

java后端，iview前端，代码后半段有controller使用参考

package com.ame.ser.utils;

import lombok.Data;

import java.util.ArrayList;
import java.util.List;

/**
 * 树节点工具类
 * @author SWJ
 *
 */
@Data
public class TreeNodeForVueUtile {
    private  String title;
    private  String id;
    private  String parenIid;
    private  List<TreeNodeForVueUtile> children;

    public TreeNodeForVueUtile() {
    }

    public TreeNodeForVueUtile(String title, String id, String parenIid) {
        this.title = title;
        this.id = id;
        this.parenIid = parenIid;
    }

    /**
     * 递归（先得到父节点）再递归
     * @param list
     * @return
     */
    public static List<TreeNodeForVueUtile> getTreeResult(List<TreeNodeForVueUtile> list){
        List<TreeNodeForVueUtile> listResult =new ArrayList<>();
        for (TreeNodeForVueUtile t:list   ) {
            if (t.getParenIid().equals("0")){
                listResult.add(t);// 得到父类
            }
        }
          secondTree(list, listResult);
        return listResult;
    }

    /**
     * 父节点获取子节点
     * @param list
     * @param listResult
     * @return
     */

    public static  void secondTree(List<TreeNodeForVueUtile> list,List<TreeNodeForVueUtile> listResult){
        for (TreeNodeForVueUtile tResult:listResult){
                List<TreeNodeForVueUtile> childrens =new ArrayList<>();
            for (TreeNodeForVueUtile t:list ) {
                if(t.getParenIid().equals("0") ){
                    continue;
                }
                if(tResult.getId().equals(t.getParenIid())){
                    childrens.add(t);
                }
            }
            tResult.setChildren(childrens);
            if(!tResult.getChildren().isEmpty()){
                secondTree(list, tResult.getChildren()) ;
            }
        }

    }

    //使用方法参考
  /*  List< TreeNodeForVueUtile> tree = new ArrayList<>();
        for (EventType e:list //原来的数据进行转换，list是原来的数据
                ) {        
        tree.add(new TreeNodeForVueUtile(e.getName(), e.getEventTypeId(), e.getParentId()));
    }
    List result =  TreeNodeForVueUtile.getTreeResult(tree);     //递归得到的结果
    */
}

data数据，给到iview的children即可